The partner of Julian Assange has urged Joe Biden to reverse the Trump administration’s decision to charge the WikiLeaks founder with espionage.

Stella Moris, who gave birth to two children by Assange during the time he sought asylum in London’s Ecuadorian embassy, spoke to the PA news agency outside HMP Belmarsh, where the Australian is being held.

Assange is involved in a court battle as the United States appeals a decision by a district judge which blocked his extradition to the US on grounds that it would be oppressive to his mental health.

A preliminary hearing is due to take place at the High Court on Wednesday.

Ms Moris said: “It’s very clear that the US administration should drop the case.

“The Biden administration can’t defend press freedom at the same time as pursue this case.

“The chilling effect its having already is diminishing our freedoms and the right of the press to be able to publish without fear of being imprisoned.

“It’s worse than hypocrisy. It’s a frontal attack on the cornerstone of what makes a country free and open and that’s something you don’t turn on and off with a switch.

“This is a dark legacy that Biden is making his own unless he reverses course and that has to be done.”

Ms Moris said despite looking noticeably dishevelled when he was removed from the Ecuadorian embassy two years ago and fears about his mental health, Assange was a “fighter” and has battled through “some very dark moments” during his time in prison.

Assange was indicted on 17 charges of espionage by a United States grand jury in 2019 after his asylum was terminated by Ecuador and he was arrested by the Metropolitan Police.

If extradited and found guilty of these charges, he faces a sentence of up to 175 years in prison.